It is known that in the case of compressed metallic gaskets such as cylinder head gaskets, particularly in the case of the sheet of a single-sheet gasket or one of the active sheets of a multi-sheet gasket, the stress zones are located around the tightening points.
These zones are thus relatively concentrated and cause differences in the distribution of applied pressures. As such, possible tightness differences occur in certain zones.
One solution to this problem consists of increasing the tightening pressures. Such a solution, however, is generally not satisfactory because the difference in pressures subsists. Moreover, an increase in tightening pressures requires a resizing of the parts which is contrary to the goals generally pursued by the automobile industry, at least in terms of light weight.
Thus, to re-establish a distribution equilibrium, it is known to use stops. These stops pick up the stresses in certain distinct zones of tightening points to homogenize the charting or tightening pressures.
Although many approaches have been proposed to create these stops, they are not all satisfactory, particularly from the cost perspective. In fact, gaskets equipped with such stops must give convincing results in terms of equilibrium distributions of tightening stresses, and must be capable of being fabricated rapidly, inexpensively, and with satisfactory reproducibility.
It is also known in the industry that the recovery of parts for complementary fabrication steps is highly penalizing from the standpoint of management, and particularly because it causes major cost increases.